Do you have a source that every country/people thinks, they are better then the others? What means better, in which kind?
I heard people talking, we are different, but rare, they are better. Germans are an exception.
Do you have a source of that claim?
You don’t, because it’s absolutely bullshit! We know Persian and Arabian history and their successes.
An example of German inferior complex, a proverb. “Am deutschen Wesen, soll die Welt genesen.“
Another example. “Deutsche Leitkultur.”